Let merge set the default strategy.
Let merge set the default strategy.

If the user does not set a merge strategy for git-pull,
let git-merge calculate a default strategy.

[jc: with minor stylistic tweaks]

Signed-off-by: Mark Hollomon <f0da38e4a13c543d4d725081fdd6bcfd57bea44e@comcast.net>
Signed-off-by: Junio C Hamano <dc50d1021234060e53ec42a77d526afa2fe07479@cox.net>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git